One of Michael W. Twitty’s most well-known and central ideas is that your food is your flag. For Twitty —  a Black, Jewish author and culinary historian from the South — compiling his flag means exploring food from the African Atlantic and Jewish diaspora civilizations. He does this in his new book, “Koshersoul,” out on Aug. 9. The World’s Bianca Hillier speaks with Twitty to hear more.